2021 年 19 巻 p. 24-31
Bismuth oxide/indium oxide microspheres have been synthesized by a facile ethylenediaminetetraacetic acid (EDTA)-assisted hydrothermal process using sodium bismuthate and indium nitrate as raw materials. The obtained products were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and solid ultraviolet-visible diffusion reflectance spectroscopy. XRD and SEM observations show that the obtained microspheres consist of tetragonal Bi2O3 and cubic In2O3 phases with a smooth surface and diameters between 150 nm and 1 μm. EDTA, hydrothermal temperature, and reaction time play essential roles in the formation of the bismuth oxide/indium oxide microspheres. The tetragonal Bi2O3 and cubic In2O3 phases are formed with increasing the hydrothermal temperature and the reaction time. Photocatalytic performance of the bismuth oxide/indium oxide microspheres was evaluated by photocatalytic degradation of rhodamine B in an aqueous solution with solar light irradiation. A rhodamine B degradation ratio depends on the solar light irradiation time and the microspheres dosage. Rhodamine B with 10 mg L−1 can be entirely removed by more than 10 mg of the bismuth oxide/indium oxide microspheres in the 10 mL aqueous solution under solar light irradiation for 6 h.